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electrical problems

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Michael-YUL, Dec 5, 2020.

  1. Michael-YUL

    Michael-YUL Junior Member

    Joined:
    Jan 15, 2018
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    Location:
    Montreal, Canada
    Vehicle:
    2009 Prius
    Model:
    Base
    Back in September, I left the headlights on in my 2009 Prius while parked a few minutes and it wouldn't start again. I got a jump and continued on my way. Since similar incidents occurred once or twice in the past year, I decided to get a new 12V battery.

    About two months later, I started getting a chime when getting out of the car, as if I had left the keys in and the door opened (was using SKS at the time). This went on for a couple of weeks, I couldn't find the source of the chime. The car then sat idle for a week and then wouldn't start, battery was completely dead.

    I got a jump and it started again. I drove for at least 30 minutes every day (I didn't charge the battery like I should have, didn't know it at the time). The door chime issue came back at some point during the week. Voltage was low, like 9 something off and 10 something on ready. On day 7 the car would not start again.

    I trickle charged the battery (Canadian tire automatic trickle charge, was on 2 amps most of the time), took about 15 hours. After running a bit, I checked tech stream, there weren't any codes (battery was unhooked for charging so makes sense, check engine light never came on). I turned off SKS thinking that it was maybe draining the battery (my driveway is pretty close to my house, also, two other toyotas were parked next to my car for the last month or so, not sure if that has anything to do with it)

    Next day the speedometer display was dark when starting. Battery voltage was 12.6. I disconnected the battery and reconnected it, speedometer display lit up again.

    Two weeks go by without any issue. No check engine light. I checked the voltage every couple of days, always above 12 when sitting, above 13 when in ready.

    This morning the speedometer display was dark. Car would not shut off with the power button. I held the power button for a bit and then was able to pull the keys out. I disconnected/reconnected the battery and the display came back on. Battery voltage is still normal. Techstream shows B1421, B1443, B1271, and C1300 (which to my amateur understanding, don't seem to be related).

    I thought that maybe the inverter was not charging the 12V battery, but after two weeks the voltage on the 12V is still normal (maybe it takes longer to drop?). I'm also not sure where the speedometer cluster going dark fits in... I've read that this can be related to a weak 12V.

    Any thoughts greatly appreciated. This forum has been an awesome help for me over the years, thanks a lot!
     
  2. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
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    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    It sounds like a failing combination meter, there are threads for DIY fixes, or you can get one with a lifetime warranty :

    Prius Speedometer Replacement
     
  3. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
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    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    My Speedo failed 2 years ago bought a rebuilt one from matt@texashybrids
    A long time member here still running good.

    go to YouTube search

    Prius combo

    there’s a good video I used to replace mine the dash tear down tutorial.
    It’s harder than it looks.
     
  4. Michael-YUL

    Michael-YUL Junior Member

    Joined:
    Jan 15, 2018
    5
    2
    0
    Location:
    Montreal, Canada
    Vehicle:
    2009 Prius
    Model:
    Base
    thanks, I called texashybrids this morning, super helpful. I'm going to try pulling out the combo meter, have to wait for a day that its not too cold so I don't break the plastic pieces. Not looking forward to this.
     
  5. edthefox5

    edthefox5 Senior Member

    Joined:
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    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Your going to break plastic pieces mostly the garnish around the vents. Its impossible not too its just age.